Color select valve for spray guns



May 13, 1969 R. s. HEDIN COLOR SELECT VALVE FOR SPRAY GUNS INVENIOR.Rosa-er S. l/azwv Filed Oct. 12. 1966.

May 13, 1969 R. s. HEDIN 3,443,578

COLOR SELECT VALVE FOR SPRAY GUNS Filed Oct. 12, 1966 7 Sheet 2 of 2P/POMJMMFD OR M00004 SP/Pfl 601V 1 N VEN TOR.

B Y J/ M W LMWM United States Patent 3,443,578 COLOR SELECT VALVE FORSPRAY GUNS Robert S. Hedin, Minneapolis, Minn., assignor to Programmed &Remote Systems Corporation, St. Paul, Minn., a corporation of MinnesotaFiled Oct. 12, 1966, Ser. No. 586,102 Int. Cl. F161: 25/02, /22, 5/12US. Cl. 137-240 3 Claims ABSTRACT OF THE DISCLOSURE The presentinvention has relation to multiple passageway valves and moreparticularly to a valve for controlling the How of one of a plurality ofdiflferent colors of paint to a spray gun in response to remote signals.

The present invention provides for remote operation of a valve assemblyto direct one of a plurality of colors of paint to a spray gun. Moreparticularly, it relates to a valve which is manufactured convenientlywithout close tolerances and yet will operate satisfactorily inautomatic paint spraying installations. Each of the paint colors iscontrolled by a separate valve mounted in the valve body, and also,means are provided for purging or cleaning the paint passageways when adifferent color paint is to be used.

The device is adapted readily to either manual or automatic operationand can be used with any type of conventional spray gun. The multiplepassageway valve is designed to be extremely economical to make, compactin size and designed to use a minimum of solvent in purging the gun andpassageways between colors. Further, it is designed so that there is aminimum of color intermix ing when diiferent color paints are usedinterchangeably.

Therefore, it is an object of the present invention to present acompact, easily manufactured, multiple passageway valve assembly.

It is another object of the present invention to present a multiplepassageway valve assembly for paints which includes means for purgingthe passageways when different color paints are to be used.

It is another object of the present invention to present a multiplepassageway valve having individually controlled ports that are capableof being operated remotely in response to a pre-programmed signal, or inresponse to manual operation.

It is still a further object of the present invention to present amultiple passageway valve body wherein the valving assembly can easilybe inserted and removed from the valve body.

It is another object of the present invention to present a multiplepassageway valve assembly for controlling a plurality of different colorpaints which has a separate system for purging the valve assembly andthe spray gun after a painting operation.

It is another object of the present invention to present a multiplepassageway valve assembly wherein the valves are arranged in an annularring around the valve body and wherein the purging system is centrallylocated in the body.

3,443,578 Patented May 13, 1969 It is still a further object of thepresent invention to present a multiple passageway valve body for paintswherein the valves themselves are arranged in an annular ring around thebody and wherein the valves are used for controlling a constantlycirculating paint supply at each of the valves, thereby having inletsand return paint conduits to each of the valves.

Other objects are inherent in the specification and will become apparentas the description proceeds.

In the drawings,

FIGURE 1 is an end elevational view of a valve assembly with parts insection and parts broken away;

FIGURE 2 is a longitudinal sectional view of a valve assembly madeaccording to the present invention taken as on line 2-2 in FIGURE 1 andincluding a schematic representation of certain components; and- FIGURE3 is a sectional view taken as on line 33 in FIGURE 2.

Referring to the drawings and the numerals of reference thereon, a valveassembly illustrated generally at 10 includes a main valve housing 11having an open interior chamber 12 and a plurality of annularly disposedchambers 13 around and adjacent to the outer periphery thereof. Asshown, an annular groove 14 is defined in the housing, and this actuallyseparates the chambers 13 into two sections so that there is an openarea in the middle area of each of the chambers 13 or, in other words,between the sections of the chamber. The chambers 13 extend in axialdirection along the length of the housing. A cover member 15 issealingly attached to one end of the housing and the cover member has anannular groove or chamber 16 defined therein. The chamber 16 aligns withall of the chambers 13 and acts as a collector chamber. An outletconnection port 17 is provided in the cover member 15 and this portopens into the annular groove or chamber 16. The port 17 is used forattachments of conduits leading. to a spray gun illustratedschematically at 20. The spray gun can be of any usual or preferredconstruction.

As shown, the valve body has sixteen of the chambers 13 arranged aroundthe periphery thereo f. A separate, constantly open paint inlet port 21is provided at each of the chambers 13 on the outer surface of the valvebody. The ports 21 open into passageways 22 (one for each of thechambers 13) which extend inwardly in radial direction for a shortdistance and then go parallel to the chainbers 13 in direction away fromthe cover member 15. The passageways 22 terminate at the outer end ofthe valve body and a separate paint line illustrated at 23 is connectedto each of these passageways 22 at the outer end thereof. The ports 21are connected to paint lines 24 leading from a pump 25 which in turnpumps paint from a supply 26 through the port 21 and into the chambers13, out through passageways 22 and then through the lines 23 back to theparticular paint supply.

A separate set of paint conduits and a separate supply is used for eachof the chambers 13, and therefore each of the chambers can handle adifferent color of paint. The return lines 23 can have restrictionstherein to maintain the pressure in chambers 13 above that in ringchamber 16 or at the spray gun.

Each of the chambers 13 houses a separate control valve assembly 30. Thevalve assemblies are all identical and are shown typically in FIGURE 2.The valve assembly 30 includes a valve seat member 31 which sits insidethe chamber 13 adjacent the cover member 15. As shown, the valve seatmember 31 has a neck portion 32 that fits inside a narrowed portion ofthe chamber 13. The neck portion includes a valve seat face 33 definedat the end of an interior chamber in the valve seat member and the seat'face surrounds a valve controlled port 34 which communicates with theannular groove or collector chamber 16 in the cover member 15. The neckportion 32 also has openings 35 which communicate with the port oropening 21 and passageway 22 to permit paint to flow through theinterior of the valve seat member and out through the passageway 22,when the port 34 is closed.

The rear portions of the valve seat member have internal threads 36 intowhich a packing nut 37 can be threadably mounted. Suitable packing 38 isplaced into the interior chamber of the valve seat member and thissurrounds a needle valve 40 which is mounted for longitudinal slidingmovement with respect to the packing nut and with respect to the valveseat member 31. As shown, the end of the needle valve adjacent port 34is tapered and mates with the valve seat face 33 so that when they arein contact, flow through port 34 is shut off.

An additional lubricating packing 41 is utilized with the needle valveto keep it lubricated.

The rear portion or section of chamber 13 comprises a cylinder section54 for mounting the actuating devices for the needle valve 40. As shown,a collar 42 is mounted against a shoulder in the chamber 13 and thiscollar 42 has an O-ring 43 which fits against the needle valve 40 andseals the interior of the rear portion of the chamber 13 from theatmosphere. A piston member 44 is slidably mounted in the chamber 13 andmounts the needle valve 40. As shown, a set screw 45 is used for fixingthe needle valve with respect to the piston and as shown the needlevalve can be provided with a head to hold it in place. The piston isalso sealed with respect to the outer surface of the cylinder portion ofchamber 13 with an O-ring 46. A spring 47 is mounted within a providedrecess in the piston 44. A cover ring 50 is fastened to the valve bodymember 11, and is of size to cover the chambers 13 at that end of thevalve body. As shown, the ring 50 then holds the spring 47 in place, andthe spring 47 urges the needle valve in direction as indicated by thearrow 51 so that it will seat down against the valve seat face 33 andnormally hold the port 34 closed.

An inlet 53 is provided into the interior of the cylinder section 54between the collar 42 and the inner end of the piston 44. A conduitshown schematically at 55 leading from a solenoid valve 56 which in turncontrols air under pressure from a source 57 is connected to the inlet53. The solenoid valve 56 (there is one actuating valve for each of thechambers 13) is controlled either by a pre-programmed device whichautomatically turns the valve on or oil? in response to an externalsignal or by manual controls illustrated schematically at 60.

Whenever a particular color of paint is desired in the spray gun, theproper control is actuated and the solenoid valve 56 for the proper oneof the chambers 13 is energized directing air under pressure into theconnected cylinder 54.

Once fluid under pressure is introduced into the cylinder 54, this willforce the piston 44 in direction opposite that indicated by the arrow 51moving the needle valve 40 away from the valve seat at 33 and openingthe connection between the inlet 21 for the paint and the port 34 sothat the paint (which is under pressure from restrictors) will flow intothe annular chamber 16, and out through the port 17 to the spray gun 20.This particular color of paint will then be sprayed from the gun.

It can easily be seen that the device can be programmed to dispense anyparticular color desired. When the spray pattern is finished, thesolenoid valve 56 will be deenergized permitting the spring 47 to returnthe needle valve to its seat and closing off that port 34.

In order to clean the chamber 16, and the spray gun and conduits ofpaint, a solvent and air purge is used. This is done by directing airunder pressure with a solvent aspirated into the air stream through asolenoid valve control 62 which also can be controlled from theprogramming or manual control 60, or separate controls tfor firstsolvent and then air according to the needs of the user. The solenoidvalve will direct the solvent and air through a conduit illustratedschematically at 63 into a fitting 64. The fitting 64 opens into apassageway 65 defined in the valve body. A ball check valve 66 held inplace with a spring 67 seats against the interior edge of the fitting 64to seal off this passageway 65 when there is a back pressure in thepassageway. The passageway 65 extends radially outwardly between two ofthe chambers 13 and opens into the annular groove or chamber 16 as shownat 68.

Thus, solvent and air under pressure from the source illustratedschematically at 69, once the valve 62 is opened, will go through thefitting 64, unseat the ball check valve 66 against the action of spring67 and this solvent and air mixture will pass through the passageway 65into the annular chamber 16 and out through the conduits to the spraygun 20. The solvent and air will clean out the passageways so that allof the previous paint will be removed. The solenoid valve 62 will thenbe shut olf and the next color of paint can be sprayed through the gunmerely by actuating the control for the desired solenoid valve 56 or byhaving this done automatically in a pre-programming system.

By arrangement of the chambers 13 annularly around the center of thevalve member and by having full flow of paint through the chambers 13, agreat saving in space is effected.

Also, by using valve seat member inserts in the chambers 13, the cost ofproducing the valve assembly is reduced because precision machining doesnot have to be done inside the bores of the chamber 13.

It should be noted that normally the spray gun will have an on-oifcontrol so that the color of paint can be selected by actuating one ofthe needles 40 before the paint is actually dispensed. Then, when thegun control is actuated, the paint will be sprayed.

What is claimed is:

1. A valve assembly for controlling discharge of any one of a pluralityof colors of paint through a single conduit from a plurality of supplylines, said valve assembly comprising a cylindrical body, a plurality offirst chambers defined in said body and arranged with their axessubstantially parallel and lying in annular orientation spaced from andaround the axis of said body, an annular tubular groove defined in anend portion of said body and forming a collector chamber, each of saidfirst chambers being open through a separate control port coaxial withthe first chamber to said collector chamber, said single conduit beingalso open to said collector chamber, means delivering a separate supplyof a different color of paint to each of said first chambers, said paintbeing maintained under pressure greater than atmosphere in said firstchambers, each of said first chambers being divided into first andsecond sections, said first section including said control port andseparate paint supply inlet and return ports, a separate valve member ineach of said first sections, said valve members each being movable froma valve seating position closing the control port leading to saidcollector chamber, to a position wherein said control port leading tosaid collector chamber is open, said second sections each comprising acylinder housing, a piston in said housing and operably attached to thevalve member in the associated first section, bias means to urge saidvalve members toward the valve seating position, means to selectivelyadmit air under pressure to each of said cylinder sections of saidchambers to move said pistons in direction against said bias means tomove the associated valve members to open position, and separate meanspositioned within the annular ring of first chambers to supply a paintsolvent to said collector chamber.

2. The valve assembly according to claim 1 further characterized in thatsaid supply inlet port and supply outlet port in each of said firstsections are unaffected by movement of said valve member, and means tocirculate the supply of paint through said first sections from the inlet5 6 port to the outlet port Whenever the control port for the ReferencesCited associated first section is closed. UNITED STATES PATENTS 3. Thevalve assembly of claim 1 further characterized in that solvent issupplied from a solvent source through g gg a centrally locatedpassageway positioned within the space 5 324O225 3/1966 Barrow; boundedby said first chambers in their annular arrange- 3373762 3/1968 Kurchak155 XR ment, a radial passageway in said housing leading from u saidcentrally located passageway to said collector cham- JOHN PETRAKES,primary Examiner ber, and check valve means in said centrally locatedpassageway to prevent paint from moving from the collector 10 U.S. Cl.X.R. chamber to said solvent source. 137602, 606

